For everyday backtesting, the current (sensible) portfolio 'limitation' (number of backtests) is find and dandy. If we're automating, then there's a case for 'bigger' (more backtests included) portfolios, as 'the more blended the mix, the smoother the flavour (and, hopefully, profit curve). For roobot-subscribers: maximum no. of backtests in a Portfolio - 100 But let's keep it sensible (and not blow up the servers!): 100 mega-pOOrt runs a month; OR (?) max. 20k trades in a mega-pOOrt backtest